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    <title>Document</title>
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<script>
    //创建一个number类型的包装类
    var num = Number(3);
    var s = 2;
    console.log(num);
    console.log(typeof num);
    console.log(s);
    console.log(typeof s);
    s.hello = "1233";
    console.log(s.hello)
    console.log(num.hello="1111");
</script>
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